The major technological change in controls is in communication
between machines with different controls, says Rex Ferguson, director of
marketing and product development, Motion Control Div, Allen-Bradley Co.
"At IMTS-88, people talked about those abilities, but didn't
really have them. Now, the architecture is there; information passes
freely between machines. The CNC can now communicate to a network, host
computer, or other device."

Previously, the few controls that could do this did so only on a
very-slow-speed basis, he notes. "Today, you have three or four
communication options on a machine. That, coupled with greater user
sophistication, has a big bearing on what people are buying today."
Although Mr Ferguson admits this doesn't mean much yet for the
small shop, it's critical for medium and large shops. "People
getting into cells or lining up machines to work together need this
communication."

"At IMTS-88," he continues, "we talked about 32-bit
processors, soft keys, menu-driven, operator interface, tool-path
graphics, color screens, etc. Today, all those things are givens."
Although "user friendly" has become an overworked term,
controls manufacturers continue striving to make their offerings easier
for the operator to use. "In the past," he admits, "some
programming was difficult, and we had to do a lot more training before
the buyer was able to use our controls."

The controls market remains three tier, based on three distinct
types of machine tools:

1. Low-end machine tools are capable of two to four axes of control
with minimal integrability to other automation products. They are
usually standalone tools with no communication capabilities. 2.
Mid-range controls typically handle six axes or more, with four of these
dedicated to the machine itself and the remainder for a toolchanger,
part loader, etc. These controls need some level of local-area-network
communication and ties to other automation products, ranging from
programmable controllers to full communication networks. 3. High-end
users continue pressing upward to aerospace machines with as many as 21
axes, with up to 14 of these within the CNC itself, a high level of
integrability, and high-speed, high-instruction-rate machining. The
leading-edge buzzwords today are such things as minimum block-cycle
times of 10 msec and servo update times of 1 msec.

Performance criteria, Mr Ferguson explains, go up with each product
range. To be a world-class player in each of these markets, a CNC vendor
must meet these criteria within a window of opportunity of 24 months or
drop out.

As you move down the product-capability curve, these criteria ease
considerably. "Whereas performance is the key on the high end, the
issues at the low end become price, a complete package, one-stop
shopping, mating up with my existing controls, and operator
training."

Three becomes two

"Today," he continues, "the marketplace is driving
us toward two ranges. They want a control product that can handle
low-end machines, yet give them capability to stretch up into mid-range
product that can move into high-end."

With too many different controls on your shop floor, Mr Ferguson
says, your investment in service, support stock, training, and operator
expertise can become exponential. Recognizing this, control vendors on
the low end are moving toward, if not a standard, at least a merging of
thought or common definition of what the customer wants. "They are
now much more reluctant to introduce radically different technology,
particularly in terms of how it's serviced or how much the user
needs to know about what's inside the box, and this will be
beneficial long term."

In short, you are asking them to lower your cost and boost your
performance capabilities. "All the bells and whistles aside,"
Mr Ferguson admits, "the bottom line is how many parts, how fast,
and what quality."